Electric riveter.



W. MORAVA.

ELECTRIC RIVETER. 1,251,266' APPLlcAUon FILED 1AN.21`. 1916. Patented Dec 25,1917.

2 SHEETS-SHEET 2.

WvweZ Jfforcww.

MUM

WENSEL MORAVA, 0F CHICAGO, ILLINOIS.

ELECTRIC RIVETER.

Specification of Letters Patent.

Patented Dec. 25, 191 '7.

Application filed January 27, 1916. Serial No. 74,542.

To all whom it 'may concern:

Be it known that I, VnNsnL MoRAvA, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Electric Riveters, of which the following is a specification.

My invention relates to improvements in electric riveting machines, and has for one object to provide a new and improved form of riveter wherein the riveting force is developed by an electric motor. Another object is to provide means for protecting the electric motor and associated riveted parts against too great over loads. Another object is to provide means for easily and conveniently manipulating the rivet. driving mechanism and associated parts. Other objects will appear in the specification. My invention therefore is illustrated more or less diagrammatically in the accompanying drawings, wherein- Figure l is a side elevation with parts in section.

Fig. 2 is a plan view.

Fig. 3 is a section along the line 3-3 of Fig. l.

Fig. A is a section along the line 4-4 of Fig. 1.

Fig. 5 is a section along the line 5-5 of Fig. l.

Like parts are indicated by like letters throughout the several figures.

Mechanical detalls.

A is the usual type of rigid jaw construction, on -the lower member of which is mounted an anvil bar A1. The upper member or part of the jaw carries a guide head A2, in which is slidably mounted the plunger A3, carrying a screw threaded adjustment therein, and a driving bar A4 with a rivet forming head A5 in opposition to the end of the anvil bar A1.

B is a table supported partially on the upper side of the jaw A and partially on a bracket B1 projecting rearwardly therefrom. At the rear end of this table is an electric motor B2. This motor is rigidl connected by a coupling B3 to a drive sha t B2. This drive shaft is always in rotation when the motor is in rotation. Its forward end is supported in the bearing B5 on a bracket B2 on the table B. B7 is a fly-wheel mounted on the motor shaft.

C is a sleeve rotatably mounted on the shaft B2. This sleeve is rotatably mounted itself, in the two bearing sleeves Cl C2 in a house C3 which house is supported on the table B by the legs C4. The central portion of the sleeve C is formed into a driving worm C5, and between each end of the worm and the bearing sleeves C1 C2 respectively is interposed a ball thrust bearing C6.

The worm C2 is in mesh with a wormwheel C7 in a casing CS, which is supported on and projects above the casing C3. The worm-wheel is mounted on and drives a shaft C2, which shaft is carried in the bearings C1o in the casing CS.

The two ends of the shaft C9 project outwardly, the bearing C1o and carrying each a crank disk D. The two crank disks D have pivoted thereon the driving links D1. These driving links D1 are in turn pivoted on a knuckle pin D2. This knuckle pin has also pivoted thereon, the two tension toggle links D3 which are pivoted at their other ends, one on either side of the head A2. Centrally disposed between these tension links and pivotally mounted on the knuckle pin D2 is a thrust link D2, which thrust link is pivotally mounted at its lower end on the plunger A3, being pinned thereto as at D5 to hold the parts in proper relation, and having a cylindrical thrust surface DG in engagement with the corresponding cylindrical surface of the plunger A3 to take the thrust. y

E is the driving portion of an electromag netic clutch. always rotates with the shaft B2 and is provided with slip-rings E1 E2 whereby electric current is supplied to the clutch. E3 is the driven portion of this clutch and it is rigidly mounted on the sleeve C so as to always rotate with it. About the outer periphery of this member E3 is a clutch-rim E2. A brake belt E5 is anchored at one end to the table B by means of the bolt E6 and at the other end terminates in a rod E7, slidably mounted in the table B and pivoted below the table to a lever E2, which lever is adapted to be normally thrust outwardly by the spring E9 to tighten the brake on the wheel. E10 is a solenoid, which when excited by a suitable electric current resists the spring E9 and releases the brake.

F is a planetary gear housing keyed to the sleeve C. It is internally toothed as at F1. i2 is a gear concentric with the internal gear F:L and keyed to the shaft B2. F3 are It is rigidly mounted on and planetary gears in mesh both with the gear FJL and the gear F2. They are each ot them rotatably mounted on a plate F4 which closes the housing F. This plate F4 carries ra brake drum Fi and a brake band FG anchored at one end on the table B, is passed around this drum and through the table B to the lever F7 upon which it is pivoted. The lever F7 is connected by means of a link F8 to a hand lever F0 pivoted on the upper part of the jaw member A so that an upward movement of the hand lever will tend to lock the brake F6 upon the brake drum Fi' holding the planetary gears F3 against rotation and causing the uninterrupted rotation of the gear F2 to rotate the planetary7 pinions and thus the internal gear which by this arrangement will be reversed in the usual manner.

Electrical details.

L Il the two line wires. They terminate at the two point switch I2, which switch is as indicated in parallel with a similar two point switch I3. The current for the motor passes through the switch T2 and for the clutch and associate parts it passes through the switch I?. From the switch T2 leads a conductor Il@ leads back to the switch I2 from conductor Y leads to the motor B2. The return conductor 17 leads to the starting box I5 and the conductor I8 leads from the starting box to the solenoid I2 whence a conductor T10 leads back to the switch I2 from, thus, when the switch 12 is closed and the starting box has been operated, the motor operates on a closed circuit included in which is the solenoid l. This solenoid is a part ot' a circuit breaker7 which circuit breaker is peculiar in that an over load on the motor operates the solenoid not to break the motor circuit but to break the clutch circuit now to be described.

A conductor K leads from the switch T2' to the terminal K1. A terminal K2 is in opposition to the terminal K1 on the lever F2. The conductor K3 leads therefrom to a switch K4. This switch is controlled by a solenoid oi circuit breaker I9. A conductor K5 leads from this s iitch to a brush KG in opposition to the slip-ring El on the clutch E. A brush K7 is in engagement with the slip-ring E2, and a conductor K'c5 leads therefrom toA the switch K9. This switch KJ is adapted to be broken by either one ot the two buttons K10 K11 on one of the disks D. A conductor K12 leads from the switch K9 back to the switch 13. A short circuit is formed by the conductor K`L3 which leads from the conductor K8 to the switch K1* on the lever F2, and a conductor Kl5 leadsl therefrom to the conductor I 12 so that even when one of the buttons K10 K11 has broken the circuit at the switch K9, the operator may by manipulating the switch K14 close that circuit, thereupon the spring shown normally keeps the switch open. K16 K17 are conductors leading` respectively from the conductors K5 K3 to actuate the solenoid El, which is thereby arranged in parallel with the clutch E so that the solenoid is always energized when the clutch is in operation, and is always dead when the clutch is dead.

It will be evident while everything shown in my drawings is an operative device, still many changes might be made both in size, shape and arrangement of parts without departing materially from the spirit oiI my invention.

The use and operation ot' my invention are as follows: The operator when about to start the machine first closes the two point switch through which the motor circuit passes. He then operates the starting` boX to start the motor. l."Vhen the motor is at speed the operator throws the two point switch controlling the clutch circuit into the closed position. l/Vith the parts in the position shown he then pulls down the hand lever until the large switch carried thereby is closed. Nothing iappens however, because the circuit is broken by the button on the crank disk. The operator then in the usual manner brings the work into position with the rivet between the jaws ot the riveter. He will then press the button on the lever handle and close the circuit Jfrom the source or". supply through the clutch. The closure of this circuit causes the clutch to operate and drive the worm, the controlling spring-held brake being released by the energizing of the solenoid at the same time as the clutch goes into action. The instant that the crank disk has rotated, the switch will be closed at that point and the operator may then release the button and the process will go on.

The rotation of the crank disk will cause the knuckle pin to rotate about the pivotal point o't the two tension links on the jaw. These links will thus approach parallelism with the driving plunger, and this plunger will be forced downwardly by the compression member to drive the rivet. As soon as the disk has made a half revolution, and the driving plunger i3 at the end of its stroke, the other circuit breaking pin will come into operation to break the circuit, disconnecting the clutch and permit the springactuated brake to stop the rotation of the worm. To release the rivet the operator again presses the button and the same thing happens eX- actly on the return stroke. This process can be continued indenitely.

It it should happen that too great a resistance were encountered by the driving plunger on its downward movement, the increasein current at the motor would operate the circuit breaking solenoid, and that instead ot' breaking the motor circuit, would break the 'clutch circuit and thus stop the movement of the driving mechanism without alecting in any way the motor. Under such circumstances as these, it would become necessary to reverse the mechanism, and this the operator would do by pushing up on the lever breaking the circuit and manually tightening the brake on the planetary transmission. This would cause the outer gear to rotate in a direction opposite to the rotation of the inner gear and thus would rotate the sleeve in a reverse direction to withdraw the rivet driving plunger. vWith the plunger withdrawn the operator would close the circuit where. it had been broken by the circuit breaker and then close the circuit by manipulation of the lever. In all probability the second blow of the rivet driving member would overcome the increased resistance and drive the rivet.

1t will be noted that a flywheel is provided. The purpose of the iiy-wheel is to store energy to overcome the initial resistance of the rivet. It will be noted that the mechanical advancement of the rivet driving mechanism increases toward the end of the stroke, and the energy stored in the ily-wheel assists in overcoming the resistance of the rivet at the beginning of the stroke when the advancement is comparatively speaking, slow.

I claim:

1. An electric riveting machine having a motor adapted for constant operation, a rivet driving plunger and a drive wheel nermanently connected thereto, a clutch interposed between the motor and the drive wheel, means for operating it to move the plunger, and means carried by the wheel t'or automatically causing the disengagement of the clutch at the end of the plunger excursion toward and from the work.

'2. An electric riveting machine having a motor adapted for constant operation, a rivet driving plunger and a drive wheel permanently connected thereto, a clutch interposed between the motor and the drive wheel, means for operating it to move the plunger. means carried by the wheel for automatically causing the disengagement of the clutch at the end of the plunger eX- cursion toward and from the work, and means controlled by the operator for operating the clutch when it has been disengaged by such automatic means.

3. An electric riveting machine having a motor adapted for constant operation, a rivet driving plunger and a drive wheel permanently connected thereto, an electromagnetic clutch interposed between the drive wheel and the motor, means carried by the wheel for breaking the clutch controlling circuit when the plunger is at either' end of its excursion.

4. An electric riveting machine having a motor adapted for constant operation, a rivet driving plunger and a drive wheel permanently connected thereto7 an electromagnetic clutch interposed between the drive wheel andthe motor, means carried by the wheel for breaking the clutch controlling circuit when the plunger is at either end of its excursion, and means controlled by the operator for short circuiting the break caused by the wheel control means.

5. An electric riveting machine having a motor adapted for constant operation, a rivet driving plunger and a drive wheel permanently connected thereto, an electromagnetic clutch interposed between the motor and wheel, a yieldingly held brake adapted normally to stop the movement of the wheel, and electrically controlled means operative only when the clutch is'in operation for releasing such brake.

6. An electric riveting machine having a motor adapted for constant operation, a rivet driving plunger and a drive wheel permanently connected thereto, an electromagnetic clutch interposed between the motor and wheel, and a manually controlled reversing mechanism interposed between the motor and wheel.

7. An electric riveting machine having a motor adapted for constant operation, a rivet driving plunger and a drive wheel permanently connected thereto, an electromagnetic clutch interposed between the motor and Wheel, and a manually controlled reversing mechanism interposed between the motor and wheel, the clutch and reversing mechanism and control being coordinated to prevent simultaneous operation.

8. An electric riveting machine having a motor, a rivet driving plunger, and a drive wheel permanently connected thereto, a clutch interposed between the motor and the drive wheel and means for operating it to move the plunger, and means automatically operative for disengaging the clutch before the end of the excursion of the plunger, when the load carried by the motor exceeds a predetermined figure.

9. An electric riveting machine having a motor, a rivet driving plunger, and a drive wheel permanently connected thereto, a clutch interposed between the motor and the drive wheel and means for operating it to move theplunger, and means automatically operative for disengaging the clutch before the end of the excursion of the plunger, when the load carried by the motor eX- ceeds a predetermined figure, and manually operated means for simultaneously closing the clutch circuit and reversing the direction of drive transmitted therethrough.

10. An electric riveting machine having a motor, a rivet driving plunger, and a drive wheel permanently connected thereto, a clutch interposed between the motor and the drive wheel, means for operating it to move the plunger, and automatic means responsive to an overload on the motor for disengaging the clutch, and manually operated means for reversing the movement of the drive wheel in response to the driving power of the motor.

ll, An electric riveting machine having a motor, a rivet driving plunger, and a drive wheel permanently connected thereto, a clutch interposed between the motor and the drive wheel, means for operating it to move the plunger, and automatic means responsive to an overload on the motor for disengaging the clutch, and manually operated means for reversing the movement of the drive wheel in response to the driving power of the motor, said means comprising a plan etary transmission and clutch.

l2. An electric riveting machine having a motor, a rivet driving plunger, and a drive wheel permanently connected thereto, a clutch interposed between the motor and the drive wheel, means for operating it to move the plunger, and means responsive to an overload on the motor for automatically disengaging the clutch, a planetary transmission, interposed between the motor and the driving wheel, adapted normally to be inoperative, and manually operated means controlled by the operator for throwing said planetary transmission into operation to reverse the movement of the wheel.

In testimony whereof I affix my signature in the presence of two witnesses this 20th day of January, 1916.

VENSEL MORAVA.

Witnesses ESTHER VAN FRANK, GENEVA HIRTH.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Iatenti, Washington, D. C. 

